Waterford - It was 3:30 a.m. and the phone's incessant ringing roused Christine Bueno from sleep. At first, she thought it was an alarm and ignored it.

But the phone continued to ring.

Oct. 31, 2010, was the day of her sophomore homecoming dance, and Bueno - now a senior at Waterford High School - was at a friend's house for a sleepover.

It was also the day her life and that of her family changed.

On the other end of the line was her sister Olivia, calling to say that their mother, Myrna, had suffered three seizures and a severe brain aneurysm and was being flown by Life Star to Massachusetts General Hospital.

"I was really confused because it was so early," Bueno, 18, said recently. "I didn't really know what was going on. On the way up, my sister was trying to explain to us what a brain aneurysm was."

At the Boston hospital, Bueno followed a red line on the floor through the Intensive Care Unit to get to her mother's hospital room.

"I remember following that line," she said. "She was already in a coma and had tubes hooked up to her head, blood was flowing out and she was about to go into surgery so they could clip the vein in her brain. I spent the night there. I slept in the waiting room with my family."

Myrna Bueno was in a coma for more than a month.

During that time, their father balanced time off from work and working almost seven days a week and Bueno's older sister, Karen Bueno-Argeris, who lives in Niantic, took over the household responsibilities. Christine and Olivia, now 16, stayed home, with family and friends checking in on them periodically. Friends would stop by with dinner for the girls.

"Karen took on all the financial stuff and is basically our mom now," Bueno said. "If it wasn't for Karen, we would probably be living on the street. My dad can barely focus on his work. If we have to do something, we have to go through her, she signs our permission slips, she's helped me apply for college. It's hard for her because normally people her age with children, that's their main thing, but she's sacrificed her own life so she could take care of our family. She barely spends time with her husband or her child. Even though she's with her child every day, she's thinking about Mom and taking care of us."

In order to take care of her mother, who returned home after her stay at the hospital, Bueno has also sacrificed much of what life is supposed to be like for a senior in high school. She and her sister have to alternate the seasons they participate in sports and have an extremely limited social life. Caring for their mother every day has also distanced them from their friends.

"We were so normal before," she said. "I definitely took everything for granted back then. It's definitely really sad."

The brain aneurysm was so severe doctors that gave Myrna Bueno a 6 percent chance of survival. But she has since made progress and now remembers things like names and birthdays.

She had to learn to walk, talk and eat again and initially did not remember her daughters' names.

"One time I said, 'What's my name,' and she said 'Harry Potter' and I thought that was funny. She's come a long way though," Bueno said. "I didn't think she'd get this far. She couldn't do anything before. We just assist her in everything now."

Bueno-Argeris said last week that she knows she asks a lot of her younger sisters. She said their first priority is their mother, then a social life.

"With Christine and Olivia I kind of have to turn to them as adults. In the beginning, it was hard because we had to ask them to miss out, but I said, 'One day, you'll realize how much sacrifice you've made and how much it means to our family,'" she said.

She said she has not allowed her sisters to falter on their academics.

"I have very high expectations of them. When things like this happen, some teenagers fall back with school, and that wasn't the thing with Christine and Olivia. They're both in the honor society and get As and Bs. I expect them to graduate, get into college and have their own careers."

This fall, Christine Bueno plans to attend the University of Rhode Island with a focus on health studies.

She said her mother's health issues have made her realize that she enjoys helping people. She's also got a solid understanding of what it takes to advocate for a patient and the level of care needed in a home setting.

"I'm pretty much an expert on brain aneurysms now," she said. "It's not what teenagers normally do."